There has been increasing interest in food safety on the part of consumers in recent years due to incidents of nefarious individuals tampering with prepackaged food items. Some prepackaged items have a plastic shrink-wrap type seal around a lid of a container that must be broken in order to access the contents of the container. In the case of plastic soft drink bottles and the like having a round screw-type cap, a lower ring may be attached to a skirt of the cap with a score line. Upon twisting of the cap to remove it from the bottle, the screw threads of the bottle impede the upward movement of the lower ring, thereby breaking the ring from the skirt of the cap along the score line and allowing the consumer to fully remove the cap to access the bottle contents. A consumer purchasing such a product at a retail store should notice if the ring were separated from the remainder of the cap, indicating someone has had access to the bottle contents and may have tampered with the product.
Various designs have also been proposed for tamper resistant or tamper evident lids for round food containers, such as ice cream containers and the like. Such tamper resistant/evident lids are designed to provide a visual indication to the purchaser as to whether the lid has been peeled back or otherwise removed from the base food container to expose the contents. One particular configuration is provided in U.S. Pat. No. 5,653,382, issued to Van De Gejin et al, which shows a container lid formed with a skirt having a sufficient downward length so that the same can be curled upward to form a return bend having a radius and an upwardly directed free end. The free end of the curled skirt serves to impede the removal of the container lid once applied by abutting with a lower edge of a rim of the base container. This design has a serious drawback, however, in that the upwardly curled portion of the skirt extending to the free end tends to become uncurled at the curved return bend when the container lid is pulled upward forcefully impacting the free end with the rim. Thus, the lid could easily be removed and reapplied to a food container with the return bend re-curled to give the appearance that the lid hadn't been removed and no tampering had taken place. Other tamper resistant/evident designs are available that incorporate lid skirts with abutting members, but unfortunately, many of these position the abutting members where they may be slid past any catching portion (e.g., the rim) of a base container. As a result, any tamper resistant or tamper evident feature of such a lid may be defeated.